Apparatus for reducing the cross section of a continuous cast strand

ABSTRACT

Apparatus for reducing the cross section of a continuous cast strand includes pairs of powered rollers disposed in horizontal planes, and pairs of powered rollers, disposed in vertical planes on opposite sides of the continuous cast strand. The strand passes between the roll pairs which are moved together by fluidactuated cylinder piston mechanisms to reduce the vertical and horizontal cross-sectional dimensions of the cast strand.

United States Patent -[72] Inventors 7 Kurt Reinfeld;

Emmanuel V. Gouye, both of Pittsburgh, Pa. [21] Appl. No. 790,608 [22]Filed Jan. 13, 1969 [45] Patented Dec. 21,1971 [73] Assignee KoppersCompany, Inc.

[54] APPARATUS FOR REDUCING THE CROSS SECTION OF A CONTINUOUS CASTSTRAND 4 Claims, 8 Drawing Figs.

[52] US. Cl 7 164/270, 72/245, 164/282 [51] Int. Cl 322d 11/12 [50]Field of Search... 164/76, 82, 270, 282, 283; 72/237, 244, 245, 238;287/5207 [56] References Cited UNITED STATES PATENTS 3,543,555 12/1970Baumann et a1. 72/245 X 3,554,269 1/1971 Hermann et a1. 164/76 X 538,2684/1895 McCracken 72/238 2,042,872 6/1936 Talbot 72/238 PrimaryExaminer-R. Spencer Annear Attorneys-Sherman H. Barber and Olin E.Williams ABSTRACT: Apparatus for reducing the cross section of acontinuous cast strand includes pairs of powered rollers disposed inhorizontal planes, and pairs of powered rollers, disposed in verticalplanes on opposite sides of the continuous cast strand. The strandpasses between the roll pairs which are moved together by fluid-actuatedcylinder piston mechanisms to reduce the vertical and horizontalcross-sectional dimensions of the cast strand.

ATENTED BEEN an SHEET 2 0F 3 INVENTORS MW .Ef/NFELD PATENTED mm W SHEET3 OF 3 INVENTORS KMFT EE/NFELD [MAMA/(15L 1/ 505 5 Ear/mg APPARATUS FORREDUCING TI'IE CROSS SECTION OF A CONTINUOUS CAST STRAND BACKGROUND OFTHE INVENTION In the technique for producing rectangular continuous caststrands in machines of the low-head type, the cast strand is formed in avertical reciprocating mold, is bent toward the horizontal, then isstraightened and thereafter passes through a cutoff mechanism whichautomatically severs the cast strand into billets of desired length.These billets are then allowed to cool and are collected and stacked inan area where they are available for further metal working. The coldbillets are later reheated in a furnace and worked upon by reducingrollers until a section of the desired characteristics is produced.

The center core of the billets obtained by this casting processfrequently have undesirable center core porosities and segregations.Also, a high rate of production of small billet sections requires eithera large number of cast strands or a difficulty controlled high-castingspeed per strand at or near the point of complete solidification of thestrand center core, before the cast strand is cut into billets.

Those skilled in the art will recognize the economic advantagesresulting from in-line" reduction of a continuous cast strand.

The term in-line" reduction as used herein refers to the fact that thecross-sectional dimensions of the cast strand are physically reduced,and the strand is elongated by the apparatus of the invention while thestrand is moving steadily in a line from one portion of a continuouscasting machine to another portion.

It should be clear that the many usual operational steps, such as billetreheating and high-temperature rolling, are eliminated by passing acontinuous cast strand through an inline" reduction apparatus, such asthat of the present invention.

How the equipment of the present invention effectively accomplishesin-line reduction of the cross section of a continuous cast strand isset forth in the following description of one embodiment andmodifications of the invention, which are exemplified in theaccompanying drawings.

SUMMARY OF THE INVENTION Apparatus for reducing the cross-sectionaldimensions of a continuous cast strand comprises a pair of unitspivotally mounted on opposite sides of the cast strand; each such unitincluding a hollow shell that is journaled to a shaft about which theshell pivots; a roller is journaled to each shell and the opposed pairof rollers is adapted to contact the sides of the cast strand when theunits are moved toward each other in a controlled manner.

BRIEF DESCRIPTION OF THE DRAWING The invention is illustrated in thedrawing wherein:

FIG. 1 is a schematic view of a continuous casting machine including oneembodiment of invention in accordance with the invention;

FIG. 2 is a schematic perspective view of the embodiment of inventionshown in FIG. 1;

FIG. 3 is a sectional view along line III-III of FIG. 2;

FIG. 4 is a sectional view along line IV-IV of FIG. 3;

FIG. 5 is a schematic elevational view of a first modification of theinvention;

FIG. 6 is a sectional view along line VI-VI ofFIG. 5;

FIG. 7 is a schematic elevational view of a second modification of theinvention; and

FIG. 8 is a schematic modification of a portion of the apparatus of FIG.1.

DETAILED DESCRIPTION FIG. 1 illustrates a continuous casting machine 10including in-line continuous cast strand reducing apparatus 11 (FIG. 2)in accordance with the invention. The apparatus 11 includes a firstassembly 13, and a second assembly 15 spaced apart from the firstassembly 13.

The first assembly 13 includes a pair of first 17 and second 19 housingunits that are journally mounted. The second assembly 15 also includes apair of third 27 and fourth 29 housing units that are journaled as at 21and 23 respectively to a support frame 25. The support frame 25 may besecured in a known manner to a suitable foundation or to the ground.

Because the first 17 and second 19 housing units are substantially likethe third 27 and the fourth 29 housing units, the following descriptionof the first housing unit 17 suffices as a description of the otherhousing units ll9, 27,.and 29.

First housing unit 17 (FIG. 3) includes a frame or a hollow shell 31 towhich are journaled a plurality of shafts and gears. As viewed in FIG.4, the left-hand end of the shell 31 is journaled to a vertical pivotshaft 33 that is journaled at the bottom to a suitable support 35.

Adjacent the vertical pivot shaft 33, there is a horizontally arrangedfluid piston motor 37 that may be similar to the type of piston motormanufactured and marketed by Vickers Division of Sperry RandCorporation. The fluid piston motor 37 has a power output worm 39 thatis suitably journaled as at 41 to the shell 31. The power output worm 39meshes with a worm gear 43 that is fixed to the lower end portion of avertical shaft 45.

The vertical shaft 45 is journaled both at the bottom, in a bearing 47mounted in the shell 31, and at the top, in a bearing 49 mounted in acover 51 that is removably secured, as by capscrews 53, to the shell 31.The upper portion of the shaft 45 is formed as a spur gear 55 thatmeshes with a driven gear 57 mounted to another vertical shaft 59 thatis substantially parallel to the vertical shaft 45.

Shaft 59 is journaled both at the top in a bearing 61 mounted in thecover 51, and at the bottom in a bearing 63 mounted in the shell 31. Thelower end portion of the shaft 59 includes a pinion 65 that meshes witha shaft-mounted idler gear 67 suitably journaled in top and bottombearings 69 that are mounted in the shell 31, as suggested in FIG. 4.

The idler gear 67 also meshes with a drive gear 71 mounted to a verticalshaft 73 that is substantially parallel to the other vertical shafts 45and 59. The vertical shaft 73 is journaled at the bottom in a bearing 75mounted in the shell 31 and, at the top, in a bearing 77. The shaft 73also carries a shaped, billetreducing roller 79 that is located in anopening 81 in the shell 31, so that opposed rollers 79, of adjacentpivotable housing units 17, 19, can coact on a continuous cast strand,such as strand 101 passing between such rollers.

The top bearing 77 is mounted in a bearing block 78 that is removablymounted to the shell 31 in such a way that both the bearing 77 and thebearing block 78 can be quickly and easily removed from the shell 31.

The bearing block 78 is provided with a cover 78a, secured thereto as bylifting eyebolts 78b or in any other suitable manner, and a nut 78c isthreaded onto the upper end of the shaft 73 having a reduced crosssection at its upper end portion.

The upper end portion of the shaft 73 is provided with internallubricating oil or grease passage (not shown) and a quickdisconnect hoseassembly 78d is attached to the shaft upper end, as shown in FIG. 4.

At the bottom of the bearing block 78, there is spacer ring 78e whichengages both the shaft 73 and the bearing block 78 to maintain theseunits in spaced apart relation.

When it is desired to change the roller 79, only the hose assembly 78d,the nut 780 have to be removed and then the bearing 77 and bearing block78 may be removed. After the spacer ring 78e is removed, the roller 79may then be easily and quickly removed. A new roller may thereafter beinstalled and the other units reinstalled.

The frame or shell 31 is provided with both upper 83 and lower 85outwardly projecting clevises, each of which is adapted to cooperatewith a tongue portion 87 of a piston rod 89 that extends out of acylinder-piston assembly 91. The

cylinder-piston 91 also has a tongue portion 93 that cooperates witheach of both upper 95 and lower 97 clevises of the cooperative secondhousing 19.

The first assembly 13 is spaced a short distance apart from the secondassembly 15, as shown in FIG. 2, and between the two assemblies 13, 15,there is a transition or guide piece 99 surrounding a continuous caststrand 101 passing through the apparatus 11. At the end of thetransition or guide piece 99 nearest the first assembly 13 (FIG. 2)there is a horizontal guide roller 103 that is journaled in bearings 105mounted to the support 35, as suggested in FIG. 3. The guide roller 103supports the cast strand 101 in passing from the second assembly 15through the transition or guide piece 99 into the first assembly.

In operation of the continuous casting machine 10, a continuous caststrand 101, after being bent and straightened in apparatus 129 so thatit moves in a substantially horizontal plane, enters the apparatus 11through a guide 107. The cast strand 101 then passes between twohorizontal rollers 79 that are mounted to shafts 109 and 111 of thesecond unit 15. The horizontal rollers 79 move toward each other whenthe pair of fluid-actuated cylinder pistons 113 are activated, wherebythe continuous cast strand 101 is reduced in thickness. The horizontalrollers 79 are driven by power supplied to the piston motors 115, 1 17,that are like the piston motor 37.

In the first assembly 13, the continuous cast strand 101 passes betweenthe vertical rollers 79 that are likewise movable toward each other sothat the cast strand is now reduced in width. The rollers 79 are drivenby the powered piston motors 37 acting through the gear trains,described herein, located inside the housing 17 and 19.

As shown in FIG. 2, the third housing 27 is provided with a fixed stop119 and the fourth housing 29 is provided with an upright arm 120 whichcoacts with the fixed stop 119 to prevent the horizontal rollers 79 fromtouching each other when the cylinder-piston assemblies 113 are notunder pressure. The first 17 and second 19 housings, being pivotableabout vertical axes, do not require the same positive stop 119 andcooperative arm 120 which are associated with the third 27 and fourth 29housings.

In the continuous casting machine 10, molten metal 121 flows from atundish 122 into a vertically reciprocable mold 123 wherein the caststrand 101 is continuously formed. The continuous cast strand 101 iswithdrawn from the mold 123 by powered pinch rollers 124, and the strandpasses through a spray chamber 125 wherein cooling water is directedonto the surface of the strand 101. From the pinch rollers 124, the caststrand 101 is urged in the usual manner by rollers (not shown) towardthe horizontal, and is supported by rollers 127 of an arcuate apronstructure. The arcuate strand 101 passes into a straightener device 129wherefrom it emerges in a horizontal plane.

Upon emerging from the straightener apparatus 129, the cast strand 101enters the in-line" reduction apparatus 11 described hereinbefore andboth the vertical and the horizontal dimensions of its cross section arereduced.

FIG. illustrates a modification of the apparatus 11 described herein andincludes another form of straightener apparatus 131 disposed between aninitial in-line reduction assembly 133 and a secondary in-line reductionassembly 135.

Basically the initial in-line reduction assembly 133 includes the samepivoted housing units 137, 139, each supporting a horizontal reductionroller 141; the housing units 137, 139 being pivoted at pins 143 to asupport frame 145 bolted to a base 146.

The secondary in-line reduction assembly 135 is substantially identicalwith the first in-line reduction assembly 13 described previously hereinexcept that the support 145 is adapted to pivotally support opposedpairs of arms 147, 149. The support frame 145 also supports a horizontalroller 151 which functions in the manner of roller 103 mentionedpreviously. The secondary in-line reduction assembly likewise includes apair of opposed vertical reduction rollers 153 that are similar to therollers 79.

The pairs of pivoted arms 147, 149 are journaled to a common shaft 155and first cylinder-piston assemblies 157 interconnect arms 147 to arms149, while second cylinder-piston assemblies 159 interconnect arms 149and a support 161 to which the assembly 135 is bolted. Pairs of arms147, 149 are disposed on opposite sides of the apparatus 131.

Each arm 147, 149 of the opposed pairs of arms are interconnected by astructural member, such an an l-beam 163, to provide rigidity to thearms 147, 149. Between each pair of opposed arms 147 and 149, there isjournaled a roller 165. The pair of rollers 165 are arranged to be on asingle arc having a center in the pivot shaft 155.

The vertical 153 as well as the horizontal rollers 141 are adapted to beeasily and quickly removed, in that each roller is mounted to a shaft167 (FIG. 6) having a reduced diameter upper end above the roller 153. Abearing 169 coacts with the shaft 167 and with a bearing housing 171that is removably mounted in each one of the pivoted units comprisingthe assembly 135. As described previously herein, a spacer ring 173,cooperating with the shaft 167 and the bearing 169 to maintain the shaftcentered in the bearing housing 171.

The upper end portion of the shaft 167, above the top of the bearing 169is threaded as at 174 and coacts with a nut 175 having a projecting arm177. The nut 175 is provided with seal ring 179 that coacts with a cover181 that is secured in a known manner to the top of the bearing housing171 to seal the bearing housing 171. The nut 175 also engages thebearing 169 to hold the bearing and its housing 171 in cooperativerelation.

In operating a continuous casting machine like that of FIG. 1, butincluding the modified apparatus of FIG. 5, the cast strand 101 entersthe unit 137 which has been arranged so that the rolls 141 are spacedapart wide enough to freely pass the head end of the curved strand. Thehead end of the strand also passes between the rollers 165 which areelevated by the cylinder-piston assembly 159.

Then, by actuating the cylinder-piston assembly 159 to move the rollers165 and arms 147, 149 downward, the head end of the cast strand 101 isdisconnected from a usual starter bar 102, Then, in conjunction with thefixed horizontal roller 151 acting as an abutment, the strand is bentdownward and extends substantially horizontal.

Thereupon, the rolls 141 may be brought together by actuating thecylinder-piston assemblies 113 to reduce the thickness of the caststrand 101. The width of the cast strand may be controlled by varyingthe apart spacing of the vertical rollers 153 as described hereinbefore.

The unit 137 also may serve as a withdrawal set of rollers and, whenoperated as such, the withdrawal or pinch rollers 124 are not required.As soon as the rollers 141 have been brought into engagement with thecast strand 101, the both reduce the vertical dimension of the crosssection of the strand and withdraw and strand from the mold of thecasting machine.

FIG. 7 illustrates another modification of the way in which the reducingrollers may be mounted in a frame or housing, such as housing 183.Housing 183 is similar to the housings 17, 19, 27, 29, except that areduction roller 185 is mounted to the upper end of a shaft 189 and notintermediate the ends of the shaft 73, as shown and describedpreviously. The housing 183, however, supports the same gearing andshafting as the frame or shell 31 illustrated in FIGS. 3, 4 anddescribed herein.

The reduction roller 185 is cantilever mounted at one end of a reduceddiameter shaft portion 189, and rests against a shoulder 191 of theshaft 187. A pair of rotatable roller-retaining lugs 193 are secured tothe shaft 187 by capscrews 195, and when the retaining lugs 193 are notengaging the roller 185, as shown in FIG. 7, the roller 185 may beeasily and quickly removed from the shaft end 189. So, too, a new rollermay be easily and quickly installed on the shaft end 191, and then theretaining lugs 193 can be rotated so as to engage the roller, as shownin FIG. 7, and the capscrews 195 may be tightened to secure the roller185 in place on the shaft end 191.

FIG. 8 illustrates a modification of the apparatus of FIG. 1 thatincludes a powerassisted roller 197 mounted to a cylinder-pistonarrangement 199. The roller 197 is located between the units 13, and isadapted to move vertically.

In the arrangement of apparatus 11a shown in FIG. 8, the unit 15 servesas a reducing and withdrawing set of rollers that take the place of thepinch rollers 124. When the unit 15 is operated in this manner the headend of the cast strand 101 initially passes freely through the rollersunder the influence of a conventional starting bar like starter bar 102of FIG. 5. As soon as the head end clears the unit 15, the roller 197 ismoved downward by the cylinder piston 199, the strand coacts with roller103 and the cast strand is disconnected from a starter bar such as bar102. The cast strand is supported by the roller 103 and is directedhorizontally into the reducing unit 13.

Those skilled in the art will recognize many significant features andadvantages in the present invention, among which are that:

The in-line reducing apparatus of the invention is simple in operationand is adaptable to reduce the cross-sectional dimensions of acontinuous cast strand in only one direction or in two directions aspreferred;

Continuously cast strands having a relatively large cross section arequickly and effectively reduced in section dimensions therebysignificantly increasing the throughput capacity of a continuous castingmachine; and

The in-line reduction equipment of the invention achieves an increase inoutput production per cast strand of a given cross section, and aconsiderable improvement in product quality and as a result of reweldingthe porous central region of the strand by compression; and

The carbon segregation and other segregations in the center core of thecast strand are significantly reduced after passing through the in-linereduction equipment of the present invention.

What is claimed is:

1. In a continuous casting machine wherein a cast strand is withdrawnfrom a mold by a started bar releasably connected to the strand, theimprovement comprising:

a. a first pair of units spaced apart from a second pair of units withthe units of each pair being disposed on opposite sides of said caststrand, each such unit comprising: i. a support,

ii. a first shaft journaled in said support,

iii. a frame journaled to said shaft,

iv. a roller mounted to a second shaft carried by said frame,

v. means for rotating said second shaft and said roller, and

vi. means connecting together the units of each pair of units to urgesaid pair of units toward each other and said rollers into surfaceengagement with said cast strand to reduce one cross sectional dimensionthereof; and

b. means disposed between said first and said second pairs of unitsengageable with said strand to disconnect said strand from said starterbar and to direct said cast strand toward said second pair of unitsincluding: i. a pair of arms pivoted about a common axis, ii. a rollersupported by each arm, iii. an abutment fixed in relation to said axis,and iv. means to move said pair of arms about said common axis forcausing said rollers to engage said strand and urge it into engagementwith said fixed abutment so the strand is bent downward to extendsubstantially horizontal. The invention of claim 1 including: a. meansfor pivoting one of said arms relative to the other arm. 3. in theapparatus of claim 1, the improvement comprising: a. means for quicklyreleasing and disconnecting said roller to said second shaft. 4. Theinvention of claim 1 wherein: a. said roller is cantilever mounted tosaid shaft, and includin b. m eans to quickly detach and secure saidroller to said shaft.

1. In a continuous casting machine wherein a cast strand is withdrawnfrom a mold by a started bar releasably connected to the strand, theimprovement comprising: a. a first pair of units spaced apart from asecond pair of units with the units of each pair being disposed onopposite sides of said cast strand, each such unit comprising: i. asupport, ii. a first shaft journaled in said support, iii. a framejournaled to said shaft, iv. a roller mounted to a second shaft carriedby said frame, v. means for rotating said second shaft and said roller,and vi. means connecting together the units of each pair of units tourge said pair of units toward each other and said rollers into surfaceengagement with said cast strand to reduce one cross sectional dimensionthereof; and b. means disposed between said first and said second pairsof units engageable with said strand to disconnect said strand from saidstarter bar and to direct said cast strand toward said second pair ofunits including: i. a pair of arms pivoted about a common axis, ii. aroller supported by each arm, iii. an abutment fixed in relation to saidaxis, and iv. means to move said pair of arms about said common axis forcausing said rollers to engage said strand and urge it into engagementwith said fixed abutment so the strand is bent downward to extendsubstantially horizontal.
 2. The invention of claim 1 including: a.means for pivoting one of said arms relative to the other arm.
 3. In theapparatus of claim 1, the improvement comprising: a. means for quicklyreleasing and disconnecting said roller to said second shaft.
 4. Theinvention of claim 1 wherein: a. said roller is cantilever mounted tosaid shaft, and including b. means to quickly detach and secure saidroller to said shaft.